22 June 2020 to 2 July 2020
US/Central timezone

Freeze-in Dark Matter from Secret Neutrino Interactions

Not scheduled
20m

Speaker

Yong Du (University of Massachusetts-Amherst)

Description

We investigate a simplified freeze-in dark-matter model in which the dark matter only interacts with the standard-model neutrinos via a light scalar. The extremely small coupling for the freeze-in mechanism is naturally realized in several neutrino-portal scenarios with the secret neutrino interactions. We study possible evolution history of the hidden sector: the dark sector would undergo pure freeze-in production if the interaction sbetween the dark-sector particles are negligible, while thermal equilibrium within the dark sector could occur if the re-annihilation of the dark matter and the scalar mediator is rapid enough. We investigate the relic abundance in the freeze-in and dark freeze-out regimes, calculate evolution of the dark temperature, and study its phenomenological aspects on BBN and CMB constraints, the indirect-detection signature, as well as the potential to solve the small scale structure problem.

Mini-abstract

Dark Matter interactions via a weak scalar and its implications on freeze-in.

Primary author

Yong Du (University of Massachusetts-Amherst)

Co-authors

Fei Huang (Chinese Academy of Sciences, Beijing) Hao-Lin Li ( University of California, Irvine) Jing-Hao Yu (Chinese Academy of Sciences, Beijing)

Presentation materials